Adding telemetry for regenerating a logins encryption key

CHANGES_UNRELEASED.md

@@ -26,3 +26,9 @@ Use the template below to make assigning a version number during the release cut
     reported in [#4575](https://github.com/mozilla/application-services/issues/4575). This is
     technically a breaking change as a dictionary described in the UDL changed, but in practice,
     none of our consumers used it, so we are not declaring it as breaking in this context.
+
+## Logins
+
+### What's New
+
+  - Added support for recording telemetry when the logins encryption key needs to be regenerated.

components/logins/android/metrics.yaml

@@ -18,6 +18,50 @@
 $schema: moz://mozilla.org/schemas/glean/metrics/1-0-0
 
 logins_store:
+  # These track when we need to regenerate the encryption key which causes all
+  # local data to be lost
+  key_regenerated_lost:
+    type: event
+    description: >
+      The encryption key was regenerated because it was lost
+    bugs:
+      - https://github.com/mozilla/application-services/issues/4554
+    data_reviews:
+      - https://github.com/mozilla/application-services/issues/4582
+    data_sensitivity:
+      - technical
+    notification_emails:
+      - [email protected]
+    expires: 2022-04-18
+
+  key_regenerated_corrupt:
+    type: event
+    description: >
+      The encryption key was regenerated because it didn't match the encrypted
+      data
+    bugs:
+      - https://github.com/mozilla/application-services/issues/4554
+    data_reviews:
+      - https://github.com/mozilla/application-services/issues/4582
+    data_sensitivity:
+      - technical
+    notification_emails:
+      - [email protected]
+    expires: 2022-04-18
+
+  key_regenerated_other:
+    type: event
+    description: >
+      The encryption key was regenerated for an unknown reason
+    bugs:
+      - https://github.com/mozilla/application-services/issues/4554
+    data_reviews:
+      - https://github.com/mozilla/application-services/issues/4582
+    data_sensitivity:
+      - technical
+    notification_emails:
+      - [email protected]
+    expires: 2022-04-18
 
   # These help us understand how much the logins store is being used, and
   # whether it's succeeding in the duties asked of it.  We'll use them to

components/logins/android/src/main/java/mozilla/appservices/logins/DatabaseLoginsStorage.kt

@@ -174,6 +174,20 @@ fun recordMigrationMetrics(jsonString: String) {
     }
 }
 
+enum class KeyRegenerationEventReason {
+    Lost, Corrupt, Other,
+}
+
+fun recordKeyRegenerationEvent(reason: KeyRegenerationEventReason) {
+    // Avoid the deprecation warning when calling  `record()` without the optional EventExtras param
+    @Suppress("DEPRECATION")
+    when (reason) {
+        KeyRegenerationEventReason.Lost -> LoginsStoreMetrics.keyRegeneratedLost.record()
+        KeyRegenerationEventReason.Corrupt -> LoginsStoreMetrics.keyRegeneratedCorrupt.record()
+        KeyRegenerationEventReason.Other -> LoginsStoreMetrics.keyRegeneratedOther.record()
+    }
+}
+
 /**
  * A helper class for gathering basic count metrics on different kinds of LoginsStore operation.
  *